ORONO — The University of Maine Black Bear hockey team has allowed just 10 goals during its current seven-game unbeaten streak (6-0-1) and the improved play of the defense corps has played a crucial role in that success.

They will be challenged this weekend when the 17-10-7 Black Bears, the fifth seed, travel to take on 22-8-4 Merrimack, the fourth seed, in their best-of-three Hockey East quarterfinal series at the cozy Lawler Arena in North Andover, Mass.

The games will start at 7:30 p.m. on Friday, Saturday and, if necessary, on Sunday.

Maine must win the series to keep its NCAA Tournament hopes alive while Merrimack appears to be a shoo-in regardless of the outcome.

Maine coach Tim Whitehead has been pleased with the progress of his defense corps.

“Their rink is a lot like our rink so our defensemen are used to going back (to get the puck) and getting hit. They have the courage to take hits to make plays. That’s what makes them so good,” said Whitehead. “They have really improved. We should be able to play well in that rink given the strength of our defense corps.”

“I think we’ve been playing pretty well lately,” said senior defenseman and assistant captain Jeff Dimmen. “We went through a stretch after Christmas when we were too lackadaisical. We took too many chances. We really wanted to get back to playing good defensive hockey and create offense from our defense. We’ve also been able to hop up into the offense and help there, too.”

During the unbeaten streak, Maine’s defensemen have contributed eight goals and 13 assists. Six of the eight defensemen have registered at least a point in the streak led by seniors Josh Van Dyk (3 goals, 5 assists) and Dimmen (3 & 3) along with junior Will O’Neill (1 & 3).

Mike Cornell, one of two sophomore defensemen along with Mark Nemec, said their defensive play “has a lot to do with the forwards showing more of an interest in coming back and helping us. Everyone is thinking defense first. This time of year, everybody knows they have to step up.”

Van Dyk added, “We have to focus on protecting our net and make sure we keep the shots to the outside. We can’t let them take liberties on (freshman goalie Dan Sullivan).”

Senior defenseman Mike Banwell said Maine has “the firepower” it needs up front.

“So now we need to focus on shutting down their big guns. We’re going to have to make good reads and communicate.” he said.

Dimmen added, “We’re going to have to have good, tight gaps and take away their time and space. We’ll need to get the puck deep in their end so we play as little defense as possible.”

Junior Ryan Hegarty and freshman Brice O’Connor have been the other defensemen.

Lawler Arena has the same dimensions as Maine’s Alfond Arena (200 feet by 85 feet) although Whitehead said “I’ve got to believe their rink is smaller than that.”

“They have shallow corners there,” said Van Dyk.

“Everything happens a lot faster (than at an Olympic-sized rink) there but it’s easier to stay between the faceoff dots so the forwards don’t have as much room to be creative,” said Dimmen. “They’re a tough team to play against. They’ll get the puck in deep and come at you. They can score, too. They’re a multi-dimensional team.”

Merrimack is 12-2-1 at home this season and has averaged 4.5 goals per game there.

Merrimack senior left wing and co-captain Chris Barton and junior defenseman and assistant captain Karl Stollery said they are anxious to avenge the 4-0 and 7-1 losses in Orono two weekends ago.

“We’re pretty eager to get back at them this weekend,” said Stollery.

But they also anticipate a battle.

“It will be a physical, hard-fought series,” said Stollery. “No one wants their season to be done right now.”

“It’s going to be a pretty long series,” predicted Barton.

Barton and Stollery said the return of 2009-2010 Hockey East Rookie of the Year and leading scorer Stephane Da Costa, who missed the series in Orono with a knee injury, will supply Merrimack with a sizeable boost.

“We really missed him that weekend,” said Stollery.

“It will all come down to who works the hardest,” said Van Dyk.

Banwell said he and the other four seniors don’t want to be the first class to go four years without making the NCAA Tournament since the class of 1986.